Study of Air Pollution Due to Magnesite in Salem District
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International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: [email protected] Volume 5, Issue 5, May 2016 ISSN 2319 - 4847 Study Of Air Pollution Due To Magnesite in Salem District T.Subramani1, A.Ravi2 1Professor & Dean, Department of Civil Engineering, VMKV Engg. College, Vinayaka Missions University, Salem, Tamil Nadu, India 2PG Student Of Environmental Engineering, Department of Civil Engineering, VMKV Engg. College, Vinayaka Missions University, Salem, Tamil Nadu, India ABSTRACT Opencast mining dominates metals, ores and building stones production in India. A survey was conducted to evaluate its local atmospheric impact. Modern opencast mining involves a high degree of mechanisation of the operations. Deep hole drilling, blasting of formations and sizing by crushing of the mineral are essential activities in most large open castmines. Heavy Earth Moving Machines (HEMM) are the essential features of all large open mines. Operation of HEMM, crushers and blasting causes environmental degradation from dust, noise and ground vibration Emissions data were utilized to compute dust generation due to different mining activities. Work zone air quality, ambient air quality and seasonal variations are described revealing high pollution potential due to suspended particulate matter (SPM) and consequent impact on human health. Air pollution control measures involve planning and implementing a series of preventive and suppressive measures in addition to dust extraction systems. Different abatement measures are enumerated. Pollution control by trees, the tolerance of trees to different air pollutants and plant species useful for controlling pollution are also discussed. There is a need for wider application of dust control chemicals on haul roads. Sustainable management of pollution can be achieved by the proper implementation of suggested abatement measures.Our study is in Salem district maganesite mine which is 10 km from city. The Ambient Air Quality has been monitored around the surrounding areas of the site. At all location, the PM2.5, PM10, SOx, NOx and CO values are found to be well within the limit. As the existing air quality measured during the season reveals the air quality is well within the limit and no new source will be added due to the proposed activity. Keyword:Study Of Air Pollution Due To Magnesite in Salem District. 1.INTRODUCTION The potential health risk from diminished air quality during wildfire events is a serious social concern. Many studies document that wildfires produce various airpollutants and often report that the ambient concentration of particulate matters (PM) increases substantially during a wildfire period. Epidemiology studies reportsignificant morbidity and mortality impacts of PM, suggesting a potential for considerable health risks from wildfires. Evaluating the social cost associated withthe health damage due to wildfire events is critical to determine the optimal wildfire management policy. Assessing this economic cost consists of multiple steps. First, the change in the air quality level due to the wildfire event must be evaluated. Second, the relationship between changes in air quality and the health impacts in wildfire-smoke affected communities must be established to estimate the total change Several studies have investigated major gaseous pollutants such as tropospheric O3, CO, NO, NO2, SO2, non-methane hydrocarbons (NM-HCs), and volatile organic compounds (VOCs). The three pollutants are linked by complex atmospheric chemistry. The working group recognizes that air pollution exists as a complex mixture and that effects attributed to O3, NO2, or PM may be influenced by the underlying toxicity of the full mixture of all air pollutants. Also, various sources such as automobiles or power plants emit mixtures. These pollutants are further transformed by processes in the atmosphere. For example, ground level ozone is a secondary pollutant produced by the interaction of sunlight with nitrogen dioxide and volatileorganic compounds. Temperature and humidity are also important. Multiple components interact to alter the composition and as a result the toxicity of the mixture. Multiple components may also elicit diverse biological responses. However, only a small number of parameters is usually measured to characterize the mixture; these parameters are then used as indicators in epidemiological studies. The lack of availability of monitoring data sometimes impairs the possibility to identify the most relevant indicator for different health endpoints.The independent effects of different pollutants must be teased apart by analytic methods in epidemiological studies; experimental design rarely permits the direct characterization of particular pollutants, e.g., for NO2, it is not feasible to assess with any certainty whether the pollutant per se has adverse respiratory effects at ambient levels, since NO2 may also be an indicator of traffic emissions. In addition, NO2 and other nitrogen oxides also contribute to the generation of ozone and other oxidant pollutants and are a precursor of the formation of nitric acid and subsequently the nitrate component of PM. Volume 5, Issue 5, May 2016 Page 162 International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: [email protected] Volume 5, Issue 5, May 2016 ISSN 2319 - 4847 Thus, NO2 is both a pollutant of concern and a surrogate for other concerns. The WG recognized these complexities in its interpretation of the evidence on NO2. 1.1 PARTICULATE MATTER Airborne particulate matter represents a complex mixture of organic and inorganic substances. Mass and composition in urban environments tend to be divided into two principal groups: coarse particles and fine particles. The barrier between these two fractions of particles usually lies between 1 μm and 2.5 μm. However, the limit between coarse and fine particles is sometimes fixed by convention at 2.5 _m in aerodynamic diameter (PM2.5) for measurement purposes. The smaller particles contain the secondarily formed aerosols (gas-to-particle conversion), combustion particles and recondensed organic and metal vapours. The larger particles usually contain earth crust materials and fugitive dust from roads and industries. The fine fraction contains most of the acidity (hydrogen ion) and mutagenic activity of particulate matter, although in fog some coarse acid droplets are also present. Whereas most of the mass is usually in the fine mode (particles between 100 nm and 2.5 _m), the largest number of particles is found in the very small sizes, less than 100 nm. As anticipated from the relationship of particle volume with mass, these so-called ultrafine particles often contribute only a few % to the mass, at the same time contributing to over 90% of the numbers. Figure 1 National Average of Source Contribution Figure 2 Specimens Of Magnesite to Fine Particle Levels Showing Conchoidal Fracture 1.2 Magnesite Magnesite (MgCO3) is a carbonate of magnesium. It is usually found as irregular veins as an alteration product of serpentine ultramafic rocks and other magnesium rich rock types and formed by replacement of dolomite and dolomitic limestone. Calcium and silica are, therefore, the most common impurities found in magnesite along with Fe2O3and Al2O3. It is a very important mineral for the manufacture of basic refractories, which could be largely used in the steel industry. In commerce, the term 'magnesite' refers not only to the mineral, but also to many products, obtained by calcining the natural carbonate; e.g., caustic magnesite (magnesia obtained by calcining crude magnesite at o comparatively low temperatures, 700 to 1,000 C, and retaining 2 to 7% CO2 as carbonate) and deadburnt or refractory magnesite (magnesia obtained by calcining magnesite at high temperatures, 1,500 to 1,800o C, usually containing less 0 than 0.5% CO2). Pure magnesite calcined at still higher temperatures (1,600 - 1,800 C) to expel carbon dioxide completely is termed as 'periclase' (MgO) in the trade. 1.3 Manufacture And Use Of Carbon Dioxide Magnesite gives off carbon dioxide on strong heating and is used in preference to limestone for the production of this gas, as it contains a much greater proportion than calcium carbonate, which carries but 44 per cent. Other advantages of magnesite are that the residual magnesia left after calcination is more valuable than lime, and that the amount of heat required to drive off the carbon dioxide is much less. Considerable amounts of liquid carbon dioxide are manufactured in India from magnesite. (Figure.2) 2. STUDY AREA The present study in the high grade terrains of the Southern Indian shield is restricted to Salem district in Tamil Nadu. Geological and petrographic studies carried out on the EllF belts of Salem by the author are presented in this study.Salem has the total area of 19.94 sq kms with Lattitude of N 11˚19' to 11˚ 58' and Longitude of E 77˚ 40' to 78˚ 50'. The mine is situated at a distance of 5 km from salem town. The run of the hill range is NW-SE. The aspect is Volume 5, Issue 5, May 2016 Page 163 International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: [email protected] Volume 5, Issue 5, May 2016 ISSN 2319 - 4847 North East &South West. It has an average elevation of 278 metres (912 ft). The rivers in Salem are Thirumanimuthar, Vasishta Nadi, Kaveri, Sarabanga nadi.(Figure.4) 2.1 Site Location 2.1.1 Geology The major ore deposits in salem are Magnesite, Limestone, Granite, Bauxite. 2.1.2 Magnesite One of the world‘s best Magnesite deposit occur in Salem. The Magnesite reserves in Tamil Nadu are about 73 million tonnes. Magnesite is used mainly for refractory purposes and in chemical industries. The major Salem district based players in this field are Tamil Nadu Magnesite (TANMAG), a State Government organisation, Burn Standard, a Government of India organisation and Dalmia Magnesite. (Figure.5) 2.1.3 Limestone Tamil Nadu ranks seventh in the country in terms of production of Limestone.